Described below is a method for operating an operator control apparatus of a motor vehicle which includes detection of a position at which a touch-sensitive operator control unit is touched by an object, and the detection, by way of a pressure sensor, of a pressure with which the touch-sensitive operator control unit is acted on by the object at the position. Also described is an operator control apparatus that performs the method.
Touch-sensitive operator control units or touchpads are already known from the related art and are used for example in laptops in order to control or select functions of the laptop. The touchpads can normally determine a position of a finger by which a user touches the touchpad, thus permitting interaction with content on the screen of the laptop. For this purpose, it is for example possible for a mouse pointer on the screen to be controlled by virtue of the user using his or her finger to touch the touchpad.
Such touchpads are increasingly also used in motor vehicles in order to be able to control functions of the motor vehicle, for example infotainment components, a navigation system or a telephone. While the motor vehicle is travelling, the driving characteristics and other influences may give rise to acceleration forces which also act on the driver. The acceleration forces can influence an operator control action on the touchpads, for example an input by way of the finger on the touch-sensitive operator control unit. This can give rise to deviations between the desired input and the actual input on the touchpad. For this purpose, DE 10 2001 089 894 A1 proposes a method by way of which, despite an input deviating from the intended input, the motor vehicle functions corresponding to the intended input are executed or accessed.
It is also known from the related art for touchpads to be combined with a force sensor arrangement which determines a finger force of the user, that is to say a pressure which the user exerts on the touchpad by way of his or her finger. Triggering of a function by way of an actuating force or an actuating pressure is thus possible. This means that the user can highlight a function for example by way of a sliding movement over the touchpad and can select the function by way of a pressing action. Thus, the behavior of a conventional mechanical button can be simulated. Only when pressure is exerted on the touchpad is the respective function triggered. To further improve the subjective impression of quality during the actuation, a mechanical haptic impulse, for example a vibration, may be generated by way of an actuator. This is also known for example from FR 2 961 610 A1. Furthermore, it is also possible for an acoustic tone, for example a click sound, to be generated by way of a loudspeaker during an actuation. The touchpad has virtually the same feel as a mechanical button during the actuation.
DE 10 2008 051 051 A1 presents a method for displaying information in a vehicle, in which method a subset is displayed on a display surface, wherein a size of the displayed subset is dependent on an enlargement factor.